Symptoms To Watch For In Your Dog: Lethargy

lethargy [ˈleTHərjē] – lack of energy and enthusiasm; state of sleepiness or deep unresponsiveness and inactivity

One of the most ambiguous and yet extremely important symptoms to watch for in dogs is lethargy.

The quieter your dog gets, the more serious the situation is. 

Symptoms To Watch For In Your Dog: Lethargy

But lethargy doesn’t tell you anything about the reason behind it. 

Anything that will cause your dog feel unwell can result in lethargy.

While other symptoms might give you SOME indication as to what could be going on, lethargy will tell you NOTHING about the cause at all.

That’s why when your dog becomes severely lethargic or the lethargy persists for more than a day or two, you do need to see a veterinarian.

You may notice other symptoms to go with the lethargy or you may not.

The other day Cookie woke up in the morning quite lethargic. With her, in particular, the change was alarming.

First thing I did was to check her vitals, her gums and look for the presence of other signs. 

Other than the lethargy and disinterest in food, there were none. Everything looked normal. If I had found one more worrisome sign, we’d have been on our way to the emergency clinic. Because Cookie otherwise looked good, we gave her a bit of time to get over whatever was wrong. Fortunately, she improved by the end of the day. If she didn’t, we’d have been on our way to the vet the next morning.

Conditions that can cause lethargy in dogs include the following:
  • Trauma
  • Poisoning
  • Pain
  • Infections
  • Hypoglycemia (low blood sugar)
  • Anemia or other blood disorders
  • Heart disease
  • Respiratory conditions
  • Liver disease
  • Diabetes mellitus
  • Hypothyroidism
  • Addison’s disease
  • Cancer
  • Certain medications
  • Snake bites
  • Parasites
  • Dehydration
  • Hypothermia
  • Gastrointestinal problems
  • Urinary tract problems
  • Electrolyte abnormalities
  • Immune diseases
  • Neurologic and neuromuscular disorders
  • Certain eye diseases
  • Musculoskeletal diseases
I wasn't kidding when I said that virtually any problem at all can cause your dog to become lethargic, was I?

Another trap that’s easy to fall into is when changes happen gradually over time.

When your normally active and playful dog suddenly becomes lethargic, you KNOW something is wrong.

But what if your dog slowly becomes quieter and quieter, over time? 

Such gradual changes are easy to miss.

You might think your dog is just slowing down with age. But I have seen senior dogs who could outplay the youngest of them. It is not age that will slow your dog down, it is most likely pain or another medical problem. Please, do always keep that in mind.

When your dog becomes lethargic, he is talking to you.

He is saying, "I really feel like crap, please, do something." It's kind of the equivalent of a person saying, "I think I should see a doctor."

Further reading:
My Pet Is Suddenly Tired and Weak. What Is Causing This?
Dog Weakness and Lethargy: Causes and Treatments
Lethargy in Dogs

Do you know what your dog is telling you about their health?

Do you know what your dog is telling you about their health?

Learn how to detect and interpret the signs of a potential problem.

Symptoms to Watch for in Your Dog

Symptoms to Watch for in Your Dog now available in paperback and Kindle. Each chapter includes notes on when it is an emergency.

Symptoms to Watch for in Your Dog is an award-winning guide to help you better understand what your dog is telling you about their health and how to best advocate for them. 

Learn how to see and how to think about changes in your dog’s appearance, habits, and behavior. Some signs that might not trigger your concern can be important indicators that your dog needs to see a veterinarian right away. Other symptoms, while hard to miss, such as diarrhea, vomiting, or limping, are easy to spot but can have a laundry list of potential causes, some of them serious or even life-threatening. 

Symptoms to Watch for in Your Dog is a dog health advocacy guide 101. It covers a variety of common symptoms, including when each of them might be an emergency. 

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